Spring winding device



Feb. 16, 1943. c. HILL 2,311,230 I SPRING WINDING DEVICE Filed April 7, 1942 INVENTOR. CHZPL ES H/LL I BY I Patented Feb. 16, 1943 UNITED STATES PATENT ()FFlCE SPRING 'INDING DEVICE Charles Hill, Reno, Nev.

Application April 7, 1942, Serial No. 437,959

' 1 Claim.

This invention relates to spring winding devices and in particular to means employed in connection with spring winding shafts as used in watches to prevent overwinding, said device being automatic in its use and functioning without attention of the operator.

A particular object of the invention is to provide a means for preventing the overwinding and oonseqeunt breaking of springs in watches that can be applied to the winding stern of a watch without being evident, and thus not detracting from the appearance of the watch and at the same time providing a device which may be set to yield at the moment the spring becomes properly wound, so that no damage to the spring can occur from overwinding or so that no stripping of the gears can occur when the tendency is to wind the watch beyond an amount ordinarily necessary to properly tension the spring.

While I have particularly referred to the use of my device in connection with a watch, it is to he understood that it can he applied to any instrument in which a spring is wound to provide the operating force in which it is advantageous to guard against a too forceful a winding of the spring so that it will not freeze or break or cause breakage of the parts associated with the spring.

A still further object of the invention is to provide a device of the character referred to which has few parts, is simple to manufacture, can be readily incorporated in spring wound devices without materially altering the parts thereof, and which can be employed in watches without increasing the size of the parts thereof.

Changes and variations may he made in the construction shown and described without departing from the principles of the invention or sacrificing its chief advantages; hence such invention is not to be confined to the structure shown in the accompanying drawing, in which:

Figure l. is an enlarged fragmentary view of the stem portion of a watch showing the application of my invention thereto,

Figure 2 is a section taken on the line 22 of Referring to the drawing in detail, If) indicates the fragment of a watch, which includes the usual spring to be wound, intermediate winding gears, hand set and other parts con-- trolled by the stem ii. The stem It is either depressed or pulled out to position the mechanism for hand setting operation and as all these parts are well known in the art, it is not believed that illustration thereof is necessary. winding of the spring in addition to tensioning it to the breaking point causes the stripping of the winding gears and as each individual spring may vary in its tension due to variations in the tempering of the steel, it is necessary that the device as employed in each watch or device be originally set so that overwinding of the spring is prevented. To this end I provide on the upper end of the winding stem l l, a hub l2, which may be an integral part of the stem or may be suitably secured thereto in any manner desired. The hub i2 is transversely slotted as at it on its peripheral face to provide a ball seat i l formed at the intersection of a radial abutment wall it and a slanting or oblique wall it, the latter of which terminates at the peripheral surface of the hub in a rounded portion ill or radius, so that a gradual lifting of the ball occurs as the spring being wound is gradually tensioned to its safe maximum. Should the incline of the wall It, referred to hereinafter as the seat wall, be too sharp, the ball would not unseat gradually and the spring would be wound to its maximum before complete unseating of the ball would occur. It is desired to bring the spring to fully wound condition gradually and this is done by a combination of degree of slant ofthe seat wall it and the adjusted tension on a spring.

The hub it his with close sliding association into the recess or pocket it of a ball carrier is which is closed at one side as at 2% and is provided with a ball retaining hole 2 l, the ball holding portion of which is conical as at 22 to suspend the ball 23 therein so that the protruding portion of said ball rests on the seat wall ill in the ball seat i i. The ball retaining hole 2i is formed in the periphery of the carrier disk Ill and in its upper portion is threaded as at M to receive the tensioning screw stud 25, which through the medium of its screw driver slot 26 may be threaded into and out of the hole M to tension a spring 2lA disposed intermediate the stud 25 and the ball 23. The adjustment of the stud 25 varies the force with which the ball rests on the seat wall [6. As the spring of the watch or device is wound, the tension thereof increases and the spring is wound The over through the carrier disk [9, hub l2 and stem H until the tension approaches maximum, at which time the ball gradually rides up on the seat wall l6 and onto the periphery of the hub as the spring is fully wound and continued winding movement of the carrier disk l9 will not produce any efiect on the winding stem H. Each time that the disk l9 makes a complete revolution after the spring is fully wound, the ball will snap into the ball seat M with an audible click, thus giving the owner of the watch audible warning that the spring of the watch has been fully wound.

In order to prevent separation of the parts l2 and I9, I provide a disk collar 21, split as at 28 so that it can'be passed over the stem II, which is secured to the under side of the ball carrier i9 by suitable screws 28. The collar extends over the edge of the hub l2 and prevents it from coming out of the carrier l9, when the stem is moved for setting the hands of the watch or clock.

If desired, the stem crown 30, which is usually knurled may be force fitted over the ball carrier 19 as shown in Figure 1 and the coil adjusting spring stud 25 will be covered.- The crown cap 38 will be applied after the tension of the spring 2% has been properly adjusted to coact with the tension of the watch spring to provide the winding release for which my invention is intended.

I claim:

In a spring winding'device, in combination, a winding stem having an integrally'formed cyiindrical hub portion, a groove in the periphery of said portion extending transversely thereof and comprising a radial wall disposed at an acute angle to the diameter of the hub portion to provide a ball drop and an abutment wall, and an adjacent contiguous wall gradually sloping from the bottom of the radial wall and terminating at the peripheral surface of the hub in a rounded portion, said walls at their juncture constituting a ball seat, a ball carrier of cylindrical shape presenting an inner medial recess opening at one side of said carrier to receive the hub in closely fitting relation, said carrier having a bore radially thereof providing a straight threaded portion and a ball retaining conical portion, through which a ball extends into said hub groove, a ball in the bore, a threaded plug closing the threaded end of the bore, a spring between said ball and said plug and arranged to be tensioned by adjustment of the plug in said bore, so that the ball will yieldably connect the hub and carrier for turning movement until a spring being wound by the winding stem reaches a predetermined tension, and the ball being arranged to ride along said gradually sloping wall to reach the periphery of said hub to permit free turning movement of said carrier with respect to said hub, said ball being arranged to snap into said seat on succeeding revolutions of the carrier to produce an audible signal that the Wound spring has been fully tensioned, a disk radially slotted for passage over the stem for positioning against the open side of said ball carrier and the disk extending over said hub to hold the same in place within said carrier, and means for attaching the disk to said carrier, and an externally knurled crown cap force fitted over said carrier to conceal the latter and the spring tensionlng stud plug.

CHARLES HILL. 

